The United States Environmental Protection Agency estimates that indoor air pollution may be eight times higher than indoor air pollution. A combination of research by the United States Redeer news network summed up 13 unexpected sources of indoor air pollution, and helped you to provide a pollution screening for your home. A shower. The 10-minute chlorine washing was 100 times the same water for 1 gallon (about 3.8 litres). Without filtering, ventilation, toxic chlorine would seriously pollu...